Organic light-emitting display apparatus

Abstract

An organic light-emitting display apparatus for blocking or preventing an electrode of an organic light-emitting device from being shorted with another electrode of the organic light-emitting device at the bent portions of the electrode and for blocking or preventing impurities from penetrating into an organic layer through the bent portions. The organic light-emitting display apparatus includes: a first electrode; a pixel defining layer formed to have a thickness away from the first electrode and covering edge portions of the first electrode; a light-emitting layer on the first electrode; a second electrode on the light-emitting layer; and a stepheight lowering layer over a portion where the first electrode contacts the pixel defining layer, and between the first electrode and the light-emitting layer or between the light-emitting layer and the second electrode, to reduce a bend of the second electrode over the portion where the first electrode contacts the pixel defining layer.

What is claimed is: 
     
       1. An organic light-emitting display apparatus comprising:
 a first electrode; 
 a pixel defining layer formed to have a thickness away from the first electrode and covering edge portions of the first electrode; 
 a light-emitting layer on the first electrode; 
 a second electrode on the light-emitting layer; 
 a stepheight lowering layer over a portion where the first electrode contacts the pixel defining layer, and between the first electrode and the light-emitting layer or between the light-emitting layer and the second electrode, the stepheight lowering layer being configured to eliminate a formation of a sharp edge of the second electrode over the portion where the first electrode contacts the pixel defining layer; and 
 a hole transporting layer between the first electrode and the second electrode, wherein the stepheight lowering layer is a distinct layer from the hole transporting layer. 
 
     
     
       2. The organic light-emitting display apparatus of  claim 1 , wherein a hole injection layer is between the first electrode and the second electrode, and the stepheight lowering layer is formed of substantially the same material as the hole injection layer. 
     
     
       3. The organic light-emitting display apparatus of  claim 2 , wherein the hole injection layer is integrated with the stepheight lowering layer. 
     
     
       4. The organic light-emitting display apparatus of  claim 1 , wherein the stepheight lowering layer is founed of substantially the same material as the hole transporting layer. 
     
     
       5. The organic light-emitting display apparatus of  claim 1 , wherein an electron injection layer is between the first electrode and the second electrode, and the stepheight lowering layer is formed of substantially the same material as the electron injection layer. 
     
     
       6. The organic light-emitting display apparatus of  claim 5 , wherein the electron injection layer is integrated with the stepheight lowering layer. 
     
     
       7. The organic light-emitting display apparatus of  claim 1 , wherein an electron transporting layer is between the first electrode and the second electrode, and the stepheight lowering layer is formed of substantially the same material as the electron transporting layer. 
     
     
       8. The organic light-emitting display apparatus of  claim 7 , wherein the electron transporting layer is integrated with the stepheight lowering layer. 
     
     
       9. The organic light-emitting display apparatus of  claim 1 , wherein a hole blocking layer is between the first electrode and the second electrode, and the stepheight lowering layer is formed of substantially the same material as the hole blocking layer. 
     
     
       10. The organic light-emitting display apparatus of  claim 9 , wherein the hole blocking layer is integrated with the stepheight lowering layer. 
     
     
       11. The organic light-emitting display apparatus of  claim 1 , wherein at least one of a hole injection layer, an electron injection layer, or a hole blocking layer is between the first electrode and the second electrode, and the stepheight lowering layer is formed of at least one of a hole injection layer forming material, a hole transporting layer forming material, an electron injection layer forming material, an electron transporting layer forming material, or a hole blocking layer forming material. 
     
     
       12. The organic light-emitting display apparatus of  claim 1 , wherein the stepheight lowering layer has an opening positioned to allow a direct connection between the hole transporting layer and the light-emitting layer or between a hole injection layer and the hole transporting layer in a position corresponding to a center portion of the light-emitting layer. 
     
     
       13. The organic light-emitting display apparatus of  claim 1 , wherein the stepheight lowering layer has a center portion positioned to correspond to a center portion of the light-emitting layer, and the center portion of the stepheight lowering layer has a thickness within a range to resonate light emitted from the light-emitting layer. 
     
     
       14. The organic light-emitting display apparatus of  claim 1 , wherein the stepheight lowering layer has a center portion positioned to correspond to a center portion of the light-emitting layer, and the center portion of the stepheight lowering layer has a thickness depending on a wavelength of light emitted from the light-emitting layer. 
     
     
       15. The organic light-emitting display apparatus of  claim 14 , wherein the thickness of the center portion of the stepheight lowering layer is an even multiple or an odd multiple of a half-wavelength of light emitted from the light-emitting layer. 
     
     
       16. The organic light-emitting display apparatus of  claim 1 , wherein the stepheight lowering layer is a separate layer between an organic layer on the first electrode and the light-emitting layer or between the light-emitting layer and the second electrode. 
     
     
       17. An organic light-emitting display apparatus comprising:
 a first electrode; 
 a pixel defining layer formed to have a thickness away from the first electrode and covering edge portions of the first electrode; 
 a light-emitting layer on the first electrode; 
 a second electrode on the light-emitting layer; 
 an organic layer disposed between the first electrode and the light-emitting layer or between the light-emitting layer and the second electrode, wherein a portion of the organic layer over where the first electrode contacts the pixel defining layer is thicker than a portion of the organic layer corresponding to a center portion of the light-emitting layer, the portion of the organic layer over where the first electrode contacts the pixel defining layer being configured to eliminate a formation of a sharp edge of the second electrode over the portion of the organic layer over where the first electrode contacts the pixel defining layer; and 
 a hole transporting layer between the first electrode and the second electrode, wherein the organic layer is a distinct layer from the hole transporting layer. 
 
     
     
       18. The organic light-emitting display apparatus of  claim 17 , wherein the organic layer is at least one of a hole injection layer, an electron injection layer, an electron transporting layer, or a hole blocking layer. 
     
     
       19. The organic light-emitting display apparatus of  claim 17 , wherein the organic layer is a first organic layer disposed between a second organic layer on the first electrode and the light-emitting layer or between the light-emitting layer and the second electrode. 
     
     
       20. An organic light-emitting display apparatus comprising:
 a first electrode; 
 a pixel defining layer formed to have a thickness away from the first electrode and covering edge portions of the first electrode; 
 a light-emitting layer on the first electrode; 
 a second electrode on the light-emitting layer; 
 a stepheight lowering layer over a portion where the first electrode contacts the pixel defining layer, and between the first electrode and the second electrode, the stepheight lowering layer being configured to eliminate a formation of a sharp edge of the second electrode over the portion where the first electrode contacts the pixel defining layer; and 
 a hole transporting layer between the first electrode and the second electrode, wherein the stepheight lowering layer is a distinct layer from the hole transporting layer. 
 
     
     
       21. The organic light-emitting display apparatus of  claim 20 , wherein at least one of a hole injection layer, an electron injection layer, an electron transporting layer or a hole blocking layer is between the first electrode and the second electrode, and the stepheight lowering layer is formed of at least one of a hole injection layer forming material, a hole transporting layer forming material, an electron injection layer forming material, an electron transporting layer forming material, or a hole blocking layer forming material. 
     
     
       22. The organic light-emitting display apparatus of  claim 20 , wherein the stepheight lowering layer is a separate layer between at least one of a hole injection layer, an electron injection layer, an the electron transporting layer or a hole blocking layer on the first electrode and the second electrode.